The invention relates to a U-shaped padlock structure, especially to a structure that is easy to use and employs the rotation of a lock core of a lock cylinder to drive a V-shaped cam to transversely move core pins in a rightward or leftward direction, resulting in a locking or unlocking effect by way of the engagement or disengagement of the core pins with the locking holes of the U-shaped shackle.
The main application of the locking device of the invention is to lock wheel spokes of cars, motorcycles, or bicycles to prevent theft.
As can be seen from FIG. 1, a prior art padlock is used to have a U-shaped shackle 1' with a L-shaped hook 11' at one end and an engaging notch 12' at the other end, a lock body 2' with an opening 21' at one end corresponding to the foregoing hook 11' and with a lock cylinder 3' at the other end, and a transversely movable core catch 22' provided therein so that after the engaging notch 12' of the shackle 1' being inserted into the openings formed on the lock body, turning the lock cylinder 3' to move transversely the core catch 22' into the engaging notch 12' will result in a locking effect.
There were the following deficiencies in the foregoing padlock.
1. A larger space requirement for the locking and the unlocking operations of the padlock: Such a requirement apparently conflicts with a real life in which the people who live in a crowded city often find it hard to find a parking space, thus resulting in much inconvenience for users. PA1 2. Orientation requirements for matching a shackle to a lock body due to a difference in the constructions of two end portions: When the light is weak or when in haste the users often make a mistake in fitting the shackle in the lock body in a wrong direction. Consequently, a locking operation becomes a time-consuming thing, requiring much perseverance. PA1 3. The requirement of turning the U-shaped shackle and the lock body to a certain angle for the engagement or disengagement between these two parts. This fact will lead to wear and deformation, resulting in a mismatching among the shackle, the lock body, and other relevant parts and a reduction in the service life of the padlock.
Another popular type of a U-shaped padlock on the market is shown in FIG. 2. The two ends of the U-shaped lock bar 10" are individually provided with an open-ended groove 11" with an orifice at the inner end of the groove. Inside the tubular body 20" is equipped with a flat locking plate 30" secured on a holder 21" at two ends thereof. The rotation of the locking plate 30" is activated by a lock core having a key 40" attached thereon. When the locking plate 30" is turned to a vertical position, the lock bar 10" can easily fall into the locking holes 50" of the holder 21" while the locking plate enters into the grooves 11" from the openings at the lower ends of the grooves. Again, returning the flat locking plate to the horizontal position can prevent the padlock from disengagement, as shown in FIG. 3.
Although the second type of prior art padlocks can perform the locking and unlocking functions too, it needs to grasp the tubular lock body 20" by a hand while holding a key by the other hand whenever conducting a locking operation. Then insert the key into the lock core and turn the flat locking plate to a vertical position and hold it there. At that time, users must struggle to insert the U-shaped lock bar into the locking holes and keep it there while turning the key to lock the U-shaped lock bar. The procedure is rather difficult for one who only has two hands available and remains to be overcome.